RivetKing seMi tUbUlaR Rivets - tHe loW cost

SEMI TUBULAR RIVETS
RivetKing® Semi Tubular rivets - The low cost fastener
When it Doesn’t Have to Come Apart
A Rivet is your most logical fastener, here’s why...
One of the lowest cost fasteners
Is a low cost production method
Can be used with most any material
It’s geared to most production requirements
Rivets are used in many major consumer and industrial products made today.
Designers and assemblers have long recognized that riveting is one of the least
expensive and most versatile assembly methods available.
Rivets have been successfully set in wood, metals, plastics, fiberboard, cloth and
ceramics. It is a strong fastener. All other things being equal, no other fastener - for
its size and simplicity - can equal the shear strength of a rivet.
Can be used for many purposes
Rivets are not only used to fasten two or more parts but often provide a dual function.
They have been used as pivots, hinges, levers, terminals, electrical contacts, cam
followers, decorative items and in hundreds of other ways. The only limiting factor to
the use of rivets is the designer’s imagination.
Available in a great variety of finishes
They can be made from copper, brass, steel, aluminum,
stainless steel and any material that can be coldheated. If color is desired, they are plated,
Japanned or painted.
Compared to other assembly machines, rivet setting equipment is lowest in cost.
Since the riveting operation is automatic, non-skilled operators can quickly perform
the work and lengthy training is not necessary.
Depending on the assembly, rivets can be set at extremely high speeds or to meet
the optimum production capabilities of the operator. Machines have been built to
feed several parts of the assembly simultaneously and to achieve most any degree of
mechanization necessary.
Some limitations
Tensile and fatigue strengths are lower than bolts. High tensile loads and extreme
vibrations can pull out the set.
Once set with rivets, an assembly cannot be disassembled for maintenance purposes.
While rivets can be made to close tolerances, they are not usually as highly a
precision fastener as a screw machine part may be. Where rivets are required for
close tolerance assemblies, please consult our sales department.
Anatomy of The Semi Tubular Rivet
Semi Tubular Rivet
HEAD DIAMETER
HEAD RADIUS
HEAD HEIGHT
SET EDGE
FILLET RADIUS
LENGTH
HOLE DEPTH TO POINT
HOLE DIAMETER
HOLE DEPTH TO APEX
Semi Tubular shoulder Rivet
BODY DIAMETER
HEAD
DIAMETER
HEAD RADIUS
SET EDGE
SHOULDER DIAMETER
HEAD HEIGHT
SHOULDER LENGTH
RIVET LENGTH
TENNON DIAMETER
TENNON LENGTH
HOLE DEPTH TO POINT
HOLE DEPTH TO APEX
PAGE 04
©2011 RIVETKING® RIVET CATALOG
HOLE DIAMETER
RIVET.COM | 1.800.BUY.RIVET
RivetKing® Semi Tubular rivets DESIGN CONSIDERations
RIVET DESCRIPTIONS AND DIMENSIONS
RIVET LENGTH AND CLINCH ALLOWANCE LENGTH
A portion of the rivet length is required for clinching the Semi Tubular rivet. As a general rule
of thumb this is usually figured at about 55% of the rivet diameter. Because rivets have been
standardized, we have calculated the required clinch allowances for standard rivets in the
table below.
MATERIAL 1
MATERIAL THICKNESS
MATERIAL 2
RIVET LENGTH
CLINCH ALLOWANCE
POST CLINCH
PRE-CLINCH
rivet diameter
max. clinch
allowance
1/16 3/32
1/8
9/64 5/32 3/16 7/32
1/4
9/32 5/16
3/8
.032
.062
.093
.156
.172
.218
.045
.093
.110
.156
.187
CA + WT = Rivet Length (RL)(Max.)
WT
Work Thickness
Clinch Allowance
CA
Sample: Assemble two 1/4" plates with 3/16" Dia.
WT=Rivet
T1 +T2 +T3....
RIVET LENGTH CALCULATION
RL (max)Thickness
= CA + WT
.50 (WT) Work
.25 Substrate1
.110 (CA) Clinch Allowance
To calculate
rivet length:
.25upSubstrate2
for T-375
Rivet
+ Thickness
a)+Add
thicknesses, T1+T2+(T3...) = Work
(WT)
b)=Select
desired
associated
ClinchLength
Allowance (CA)
.160
Max. Rivet
.50 (WT)
Workrivet diameter and locate=the
c) Add
Work Thickness (WT) + Clinch Allowance
(CA)(5/32)
= Maximum
Rivet Length (RL)
Thickness
.156
= Closest
d) Select rivet below the Maximum Rivet Length to the nearest 1/32”.
Example: Fasten 2 pieces of .125” thick steel with steel 3/16” (.375 head) rivets.
a) .125 (T1) +.125 (T2) = .250 (WT)
b) .110 (CA)
c) .250 (WT) + .110 (CA) = .360 (RL) Max.
d) .360 (RL) Max,... Closest standard size .360” (RL)
Rivet Size: 3/16” x 11/32” Rivet King Part# XTT3750113Z
Adding the clinch allowance value to the total thickness of the assembly to be riveted,
gives you the rivet shank length. If the rivet has a countersunk type head, the head
thickness should be included in this length.
pressures to upset a Semi Tubular rivet
To calculate the required pressure to set a Semi Tubular rivet, you will need to know the
diameter and the material of the rivet.
A= Rivet Diameter
D= Rivet Hole I.D.
MTS= Material Tensile Strength (referenced in the same table as the formula)
" "
2
−
" "
2
x
x 1.5
©COPYRIGHT 2012 RIVETKING® SEMI TUBULAR RIVET CATALOG
Typical Wire Tensile Strengths for Rivets: (Use as “MTS” for above calculation)
Steel: 80,000 psi Stainless Steel: 100,000 psi
Aluminum: 50,000 psi
Copper: 40,000 psi
Brass: 70,000 psi
1.800.BUY.RIVET | RIVET.COM
!
RIVET SETTING CLEARANCES
This is one of the most common oversights occurring in product
designs. Sufficient clearances must be provided in all directions
so that riveting equipment is able to get the rivet
into the work piece for proper clinching. Axial
access for clinching must be available both
above and below the hole through which the
rivet must pass. Clearances vary depending on
the configuration of assembly, the thickness of
assembly and the length of the rivet.
!
Hole clearances
Usually the smaller the rivet the less the clearances are required. As a general rule,
the minimum hole clearance is .003” and the maximum is .008”. When one rivet is
set in an assembly, the minimum should be observed to assure the strongest clinch
possible. If the two or more holes on an assembly are being set with rivets,
clearances on the maximum side should be used. The amount
of clearance depends largely on the ability of your
production equipment to maintain close center
to center hole location tolerances on the
mating part to be riveted.
CLINCH TYPE
There are two types of settings that are normally
used in the clinching of Semi Tubular rivets;
the Roll Clinch and the Scored Clinch. A Rolled
Clinch gives the maximum strength when the
rivets are set properly. When this clinch is used
with soft materials, washers, (burrs) or caps will
provide more bearing surface and a stronger
clinch. A Scored Clinch holds best on soft
materials since it can be turned into the material
and spreads the clinch to provide a greater
contact bearing surface.
Roll Clinch
Scored Clinch
SCORED CLINCH
Substrate 1
Substrate 2
Tolerances should be considered as actually representing degree of error.
Designs should start with zero tolerance (allowable error) being made only to fit
the product designs into the manufacturing process. Many mechanical failures
of product designs can be avoided. For example, the holes in two pieces to be
assembled are deliberately made oversized so there will be no question of the
rivet going through. However, these two pieces rotate separately around the
rivet. Because of the sloppiness in the hole, an eventual elongation of the hole
occurs resulting in the malfunction of the assembly.
ROLL CLINCH
LENGTH
CALCULATION
LENGTH
CALCULATION
tolerances
CORROSION PROTECTION
The corrosion factor of a particular rivet is dependent on the
corrosion of the base metal, the protection layer (plating) and the
conversion layer (chromate). Being that the most cost effective
material to produce is steel, most prefer to protect the steel with
a plating such as Zinc and a chromate. Rivets require a specialized
plating and wax therefore it is highly suggested the manufacturer
perform this task. For standard performance a SST rating (salt
spray test) is about 48 hours until red rust. Other platings such
as Zinc alloys (i.e. ZiNi, ZnFe and ZnTi) can extend the SST rating
to 840 hours until red rust. Our in-house test facilities can test the
rivet before and after setting according to the ASTM B117 standard.
galvanic action corrosion
Galvanic Action is seldom considered in design but it can often
be one of the hidden causes of failures. Galvanic corrosion is
accelerated electromechanical corrosion created when a noble
metal is in contact with another less noble metal, both being in
a corroding medium (such as damp air). The less noble metal
corrodes at a faster rate than normal while the noble metal acquires
greater protection of corrosion. For example, an Aluminum (less
noble metal) rivet in a copper (more noble metal) would cause
aluminum to corrode at an accelerated rate while the copper would
be virtually un-affected. Should you be in a position of having to join
two dissimilar metals, be sure to refer to the Galvanic Series table.
Riveting without prepared holes
For some applications Semi Tubular rivets can be used without the
need for preformed or pre drilled holes. Semi Tubular self-piercing
rivets can be used with materials such as leather, some plastics,
and light sheet metals. When piercing sheet metal, adjustments
may be suggested to the rivet raw material, hole diameter and
heat treatment. Self-piercing rivets can be used especially in
difficult spot welding applications, piercing and fastening in just
one step. They have excellent mechanical strength and fatigue
performance. Since Semi Tubular self-piercing rivets can be
automated, you can expect highly repeatable results.
PAGE 05
©2011 RIVETKING® RIVET CATALOG
SEMI TUBULAR RIVETS
The standard Semi Tubular Rivet is made of 3 major components with 6 dimensional values,
all of which are required in order to produce the rivet.
1) Body or Shank (Diameter & Length)
2) Head (Diameter & Height)
3) Hole (Diameter & Depth)
Custom rivets are sometimes produced with an additional component called a “shoulder”.
In this case, additional diameter and shoulder length dimensions are required for each
shoulder. Rivets can be made with multiple shoulders, however, it is suggested that Semi
Tubular rivets be designed with only one shoulder. When a shoulder rivet is required, the
hole depth should not extend into or past the shoulder, as this causes problems in the
manufacturing process and may adversely affect the functionality of the rivet.